Stabilization of vitamins in water-in silicone oil (W/O) emulsions

Abstract

A water-in-oil (W/O) emulsion with a discontinuous aqueous phase dispersed in a continuous oil phase has in the continuous oil phase a linear silicone polyether, an α,ω-diene crosslinked silicone elastomer, and a nonionic organic emulsifier. The W/O emulsion is otherwise free of silicone elastomers prepared using unsaturated compounds containing silicon atoms. Either the discontinuous aqueous phase of the W/O emulsion or the continuous oil phase of the W/O emulsion contains a water soluble or oil soluble active ingredient such as a vitamin.

1. A composition comprising a water-in-oil (W/O) emulsion having a discontinuous aqueous phase dispersed in a continuous oil phase, the continuous oil phase of the W/O emulsion comprising a linear silicone polyether, the linear silicone polyether having a rake type structure wherein the polyoxyethylene or polyoxyethylene-polyoxypropylene copolymeric units are grafted onto a siloxane backbone, or the linear silicone polyether having an ABA block copolymeric structure wherein A represents the polyether portion and B represents the siloxane portion of an ABA structure; a non-emulsifying α,ω-diene crosslinked silicone elastomer having no oxyalkylene units in its structure; and a nonionic organic emulsifier selected from the group consisting of carboxylated alcohol ethoxylates, carboxylated alkylphenol ethoxylates, ethoxylated alcohols, ethoxylated fatty acids, ethoxylated fatty esters, ethoxylated fatty oils, glycerol esters, polyglycerol fatty esters, ethoxylated glycerol esters, sorbitan derivatives, sucrose esters and their derivatives, and glucose esters and their derivatives; the W/O emulsion being free of silicone elastomers prepared using unsaturated compounds containing silicon atoms. 
     
     
       2. A composition according to  claim 1  in which one of the discontinuous aqueous phase of the W/O emulsion or the continuous oil phase of the W/O emulsion contains a water soluble active ingredient or an oil soluble active ingredient, respectively. 
     
     
       3. A composition according to  claim 2  in which the active ingredient is selected form the group consisting of Vitamin B 1 , Vitamin B 2 , Vitamin B 6 , Vitamin B 12 , niacin, folic acid, biotin, pantothenic acid, Vitamin E, Tocopherol, α-Tocopherol, β-Tocopherol, γ-Tocopherol, Δ-Tocopherol, Tocophersolan, Tocopheryl Acetate, Tocopheryl Palmitate, Tocopheryl Linoleate, Tocopheryl Nicotinate, Tocopheryl Succinate, and mixtures thereof. 
     
     
       4. A composition according to  claim 1  in which the continuous oil phase of the W/O emulsion contains 0.2-3.0 percent by weight of the linear silicone polyether, 0.2-10 percent by weight of the α,ω-diene crosslinked silicone elastomer, and 0.1-4.0 percent by weight of the nonionic organic emulsifier, the balance of the W/O emulsion containing a solvent and water. 
     
     
       5. A composition according to  claim 4  in which the solvent is a volatile cyclic alkyl siloxane with the formula (R′″ 2 SiO) d  or a volatile linear alkyl siloxane with the formula R′″ 3 SiO(R′″ 2 SiO) e SiR′″ 3  in which R′″ is an alkyl group containing 1-6 carbon atoms, d is 3-6 and e is 0-5. 
     
     
       6. A composition according to  claim 5  in which the solvent is selected from the group consisting of hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, dodecamethylpentasiloxane, tetradecamethylhexasiloxane, and hexadecamethylheptasiloxane.